scholarly journals Investigation of the Efficiency of Wet Biodiesel Purification

2020 ◽  
Vol 154 ◽  
pp. 02006 ◽  
Author(s):  
Viktor Polishсhuk ◽  
Svetlana Tarasenko ◽  
Ievgen Antypov ◽  
Nataliya Kozak ◽  
Andrii Zhyltsov ◽  
...  
Keyword(s):  
Payback Period ◽  
Main Research ◽  
Fine Grained ◽  
Biogas Plants ◽  
Blade Mixer ◽  
Biodiesel Purification

The main research aim is to verify the efficiency of wet methods of biodiesel cleaning and to establish optimal and rational parameters for biodiesel purification and disposing of its cleaning waste. The efficiency of biodiesel washing was studied by means of volumetric, bubble and aerosol washing. Volumetric washing of biodiesel was carried out with the use of a blade mixer with three blades on a shaft and a four-blade agitator with sloping blades. One of the three methods of biodiesel washing studied can be recommended for practical use – aerosol washing with medium- and large-grained washing to be carried out for at least 4-5 hours, while fine-grained – for a longer time. The use of waste from the purification of biodiesel as a cosubstrate in biogas plants will almost double the output of biogas, which will significantly reduce the payback period of biogas plants.

scholarly journals Children’s drawings as part of School Language Profiles: Heteroglossic realities in families and schools

2018 ◽  
Vol 9 (2-3) ◽  
pp. 201-223 ◽  
Author(s):  
Judith Purkarthofer
Keyword(s):  
Research Question ◽  
Close Relation ◽  
Analytical Framework ◽  
Language Practices ◽  
Children's Drawings ◽  
Main Research ◽  
Fine Grained ◽  
Children’S Drawings ◽  
Separable Spaces ◽  
Language Profiles

AbstractChild language development occurs in a given environment, complete with explicit and implicit regulations, intervening actors with their coherent or contradictory intentions, and specific resources for speakers. The main research question of this contribution is: What can drawings as parts of School Language Profiles tell us about the multilingual environments of bilingual families and schools? The analytical framework of spatial and language practices provides a means to talk about how and why certain expressions are chosen and which influences are mentioned in relation to school and family. In particular, the focus is on how heteroglossic spaces are constructed through local/spatial/language practices and how these constructions are represented in the drawings of children. The drawings were collected in a bilingual school in Austria, with Slovene and German as languages of instruction. Children’s drawings present a fine-grained perception of their multilingual surroundings and we see how children refer to home/school in their drawings and distinguish language realities. Findings indicate that language regimes and goals of families and school are in close relation to each other, have influence on each other but do not necessarily always complement each other. This means that in analyzing heteroglossic realities, both cannot be regarded as separate (or separable) spaces.

scholarly journals Efficiency of digestat of biogas plants

2020 ◽  
Vol 11 (4) ◽  
pp. 107-115
Author(s):  
V. M. Polishchuk ◽  
◽  
D. A. Derevianko ◽  
S. A. Shvorov ◽  
Ye. O. Dvornik ◽  
...  
Keyword(s):  
Biogas Production ◽  
Organic Fertilizer ◽  
Arable Land ◽  
Payback Period ◽  
Biogas Plant ◽  
Available Nitrogen ◽  
Commercial Use ◽  
Biogas Plants ◽  
The Cost ◽  
The Impact

It has been established that the digestate of biogas plants is a valuable organic fertilizer that is quickly absorbed by plants, contains a complex of macro- and microelements necessary for plant growth, has a high content of readily available nitrogen for plants, has a pH level close to neutral and does not contain viable weed seeds and pathogens. microflora. It is technically difficult to make untreated digestate into the soil, so it is predivided into solid and liquid fractions on separators. A major problem with the commercial use of digestate in Ukraine is the lack of its standardization. When applying digestate to the company's own fields, which owns the biogas plant, the standardization of its quality is not critical. However, the lack of a standard for digestate as a high-quality organic fertilizer significantly limits its use. The needs for digestate were determined to restore soil fertility and fertilize crops in and with a herd of 1,000 cattle (500 heads of dairy cows and 500 heads of young cattle and heifers) and with an arable land area of 1,800 hectares. It is established that only one ton of digestate remains for commercial use after application to the fields, the profit from the sale of which does not significantly affect the profitability of biogas production. The payback period of the biogas plant is 6.4 years and depends on the cost of biogas production. With the commercial use of all digestate produced during the year, the payback period of the biogas plant is reduced to one year and below and does not depend on the cost of biogas production, and the impact of the "green" tariff on the payback period of the biogas plant is leveled.

scholarly journals Das Verständnis grammatischer Strukturen beim Lesen in Deutsch als Fremdsprache: Ergebnisse einer empirischen Untersuchung

2010 ◽  
Vol 38 (2) ◽  
Author(s):  
Irmtraud Kaiser ◽  
Elisabeth Peyer ◽  
Raphael Berthele
Keyword(s):  
Language Proficiency ◽  
Language Processing ◽  
Systematic Investigation ◽  
Placement Test ◽  
Main Research ◽  
Third Language ◽  
Self Evaluation ◽  
Fine Grained ◽  
The University ◽  
Grammatical Structures

AbstractThis paper presents an overview of the results of the research project “The psycholinguistics of a grammar for reading German” which has been carried out at the University of Fribourg/Freiburg (CH). The project is based on the idea that the most natural and direct way to multilingualism starts with receptive competence in a third language. In the context of research into European intercomprehension, it investigates Italian and French students' grammatical problems while reading in German as an L3 or L4. To achieve this aim, we worked with specially developed experimental designs. The main research instrument was a reading test which consisted of encyclopaedia articles on imaginary animals. By way of these articles seven grammatical structures of German were tested for their receptive difficulty, with a particular focus on grammatical structures that are traditionally deemed to be difficult for learners of German as a second/foreign language. This general opinion, however, is based on teachers' experience and/or production evidence and not on a systematic investigation of comprehension processes. Further research instruments were a German placement test as well as a self-evaluation of the students' competences in reading in other foreign languages. In addition, oral translation exercises into the L1 of the participants were carried out which helped to gain further insight into the process of reading comprehension.In our paper, we will discuss under what circumstances certain grammatical structures pose problems to readers at various levels of language proficiency. On the basis of oral translation protocols, of general cognitive (language) processing mechanisms, and the structure of the German language, tentative explanations will be given as to why certain sentences/structures are more difficult to understand than others and why some structures do not seem to be a problem at all. The results of the study allow fine-grained insights into the impediments (or their absence) particular structures represent for in-depth comprehension of German texts at various levels of competence.

Application of an image management system in microscopy

1992 ◽  
Vol 50 (2) ◽  
pp. 1052-1053
Author(s):  
Richard S. Chemock
Keyword(s):  
Data Storage ◽  
Cost Savings ◽  
Image Data ◽  
Analytical Techniques ◽  
Operational Mode ◽  
Fine Grained ◽  
Image Recording ◽  
Primary Output ◽  
Capacity Data ◽  
Image Management System

One of the most common tasks in a typical analysis lab is the recording of images. Many analytical techniques (TEM, SEM, and metallography for example) produce images as their primary output. Until recently, the most common method of recording images was by using film. Current PS/2R systems offer very large capacity data storage devices and high resolution displays, making it practical to work with analytical images on PS/2s, thereby sidestepping the traditional film and darkroom steps. This change in operational mode offers many benefits: cost savings, throughput, archiving and searching capabilities as well as direct incorporation of the image data into reports.The conventional way to record images involves film, either sheet film (with its associated wet chemistry) for TEM or PolaroidR film for SEM and light microscopy. Although film is inconvenient, it does have the highest quality of all available image recording techniques. The fine grained film used for TEM has a resolution that would exceed a 4096x4096x16 bit digital image.

Use of fractals to describe microstructures of porous thick-film platinum electrodes

1992 ◽  
Vol 50 (1) ◽  
pp. 314-315
Author(s):  
Steven D. Toteda
Keyword(s):  
Fractal Dimension ◽  
Power Plants ◽  
Electrical Response ◽  
Cubic Phase ◽  
Platinum Electrodes ◽  
Fine Grained ◽  
Impedance Response ◽  
Platinum Particles ◽  
Energy Surfaces ◽  
Highly Porous

Zirconia oxygen sensors, in such applications as power plants and automobiles, generally utilize platinum electrodes for the catalytic reaction of dissociating O2 at the surface. The microstructure of the platinum electrode defines the resulting electrical response. The electrode must be porous enough to allow the oxygen to reach the zirconia surface while still remaining electrically continuous. At low sintering temperatures, the platinum is highly porous and fine grained. The platinum particles sinter together as the firing temperatures are increased. As the sintering temperatures are raised even further, the surface of the platinum begins to facet with lower energy surfaces. These microstructural changes can be seen in Figures 1 and 2, but the goal of the work is to characterize the microstructure by its fractal dimension and then relate the fractal dimension to the electrical response. The sensors were fabricated from zirconia powder stabilized in the cubic phase with 8 mol% percent yttria. Each substrate was sintered for 14 hours at 1200°C. The resulting zirconia pellets, 13mm in diameter and 2mm in thickness, were roughly 97 to 98 percent of theoretical density. The Engelhard #6082 platinum paste was applied to the zirconia disks after they were mechanically polished ( diamond). The electrodes were then sintered at temperatures ranging from 600°C to 1000°C. Each sensor was tested to determine the impedance response from 1Hz to 5,000Hz. These frequencies correspond to the electrode at the test temperature of 600°C.

Amorphous silica coating on α-alumina particles

1995 ◽  
Vol 53 ◽  
pp. 210-211
Author(s):  
J. W. Mellowes ◽  
C. M. Chun ◽  
I. A. Aksay
Keyword(s):  
Amorphous Silica ◽  
Heterogeneous Nucleation ◽  
Homogeneous Nucleation ◽  
Silica Coating ◽  
Full Density ◽  
Optimal Conditions ◽  
Fine Grained ◽  
Alumina Particles ◽  
Complete Mullitization ◽  
Powder Compacts

Mullite (3Al2O32SiO2) can be fabricated by transient viscous sintering using composite particles which consist of inner cores of a-alumina and outer coatings of amorphous silica. Powder compacts prepared with these particles are sintered to almost full density at relatively low temperatures (~1300°C) and converted to dense, fine-grained mullite at higher temperatures (>1500°C) by reaction between the alumina core and the silica coating. In order to achieve complete mullitization, optimal conditions for coating alumina particles with amorphous silica must be achieved. Formation of amorphous silica can occur in solution (homogeneous nucleation) or on the surface of alumina (heterogeneous nucleation) depending on the degree of supersaturation of the solvent in which the particles are immersed. Successful coating of silica on alumina occurs when heterogeneous nucleation is promoted and homogeneous nucleation is suppressed. Therefore, one key to successful coating is an understanding of the factors such as pH and concentration that control silica nucleation in aqueous solutions. In the current work, we use TEM to determine the optimal conditions of this processing.

Interfacial structures of dissimilar materials joined by capacitor-discharge welding

1994 ◽  
Vol 52 ◽  
pp. 534-535
Author(s):  
C. P. Doğan ◽  
R. D. Wilson ◽  
J. A. Hawk
Keyword(s):  
Rapid Solidification ◽  
Fusion Zone ◽  
Dissimilar Materials ◽  
Solidification Process ◽  
Weld Interface ◽  
Capacitor Discharge ◽  
Fine Grained ◽  
Iron Aluminum ◽  
Conductive Ceramics ◽  
Capacitor Discharge Welding

Capacitor Discharge Welding is a rapid solidification technique for joining conductive materials that results in a narrow fusion zone and almost no heat affected zone. As a result, the microstructures and properties of the bulk materials are essentially continuous across the weld interface. During the joining process, one of the materials to be joined acts as the anode and the other acts as the cathode. The anode and cathode are brought together with a concomitant discharge of a capacitor bank, creating an arc which melts the materials at the joining surfaces and welds them together (Fig. 1). As the electrodes impact, the arc is extinguished, and the molten interface cools at rates that can exceed 106 K/s. This process results in reduced porosity in the fusion zone, a fine-grained weldment, and a reduced tendency for hot cracking.At the U.S. Bureau of Mines, we are currently examining the possibilities of using capacitor discharge welding to join dissimilar metals, metals to intermetallics, and metals to conductive ceramics. In this particular study, we will examine the microstructural characteristics of iron-aluminum welds in detail, focussing our attention primarily on interfaces produced during the rapid solidification process.

TEM/AEM characterization of fine-grained clay minerals in very-low-grade rocks: Evaluation of contamination by empa involving celadonite family minerals

1996 ◽  
Vol 54 ◽  
pp. 694-695
Author(s):  
Gejing Li ◽  
D. R. Peacor ◽  
D. S. Coombs ◽  
Y. Kawachi
Keyword(s):  
Electron Microscopy ◽  
Volcanic Rocks ◽  
Analytical Electron Microscopy ◽  
Metamorphic Rocks ◽  
New Mineral ◽  
Chemical Compositions ◽  
Low Grade ◽  
Fine Grained ◽  
Depth Analysis ◽  
Mineral Aggregates

Recent advances in transmission electron microscopy (TEM) and analytical electron microscopy (AEM) have led to many new insights into the structural and chemical characteristics of very finegrained, optically homogeneous mineral aggregates in sedimentary and very low-grade metamorphic rocks. Chemical compositions obtained by electron microprobe analysis (EMPA) on such materials have been shown by TEM/AEM to result from beam overlap on contaminant phases on a scale below resolution of EMPA, which in turn can lead to errors in interpretation and determination of formation conditions. Here we present an in-depth analysis of the relation between AEM and EMPA data, which leads also to the definition of new mineral phases, and demonstrate the resolution power of AEM relative to EMPA in investigations of very fine-grained mineral aggregates in sedimentary and very low-grade metamorphic rocks.Celadonite, having end-member composition KMgFe3+Si4O10(OH)2, and with minor substitution of Fe2+ for Mg and Al for Fe3+ on octahedral sites, is a fine-grained mica widespread in volcanic rocks and volcaniclastic sediments which have undergone low-temperature alteration in the oceanic crust and in burial metamorphic sequences.

Correlation between dislocation, grain boundary and interface of duplex SS in stress corrosion cracking(SCC)

1990 ◽  
Vol 48 (4) ◽  
pp. 928-929
Author(s):  
Wang Zheng-fang ◽  
Z.F. Wang
Keyword(s):  
Stainless Steel ◽  
Thermal Cycle ◽  
Secondary Phase ◽  
Corrosion Cracking ◽  
Coarse Grained ◽  
Test Environment ◽  
Fine Grained ◽  
Evaluation Test ◽  
Welding Thermal Cycle ◽  
Micro Analysis

The main purpose of this study highlights on the evaluation of chloride SCC resistance of the material,duplex stainless steel,OOCr18Ni5Mo3Si2 (18-5Mo) and its welded coarse grained zone(CGZ).18-5Mo is a dual phases (A+F) stainless steel with yield strength:512N/mm2 .The proportion of secondary Phase(A phase) accounts for 30-35% of the total with fine grained and homogeneously distributed A and F phases(Fig.1).After being welded by a specific welding thermal cycle to the material,i.e. Tmax=1350°C and t8/5=20s,microstructure may change from fine grained morphology to coarse grained morphology and from homogeneously distributed of A phase to a concentration of A phase(Fig.2).Meanwhile,the proportion of A phase reduced from 35% to 5-10°o.For this reason it is known as welded coarse grained zone(CGZ).In association with difference of microstructure between base metal and welded CGZ,so chloride SCC resistance also differ from each other.Test procedures:Constant load tensile test(CLTT) were performed for recording Esce-t curve by which corrosion cracking growth can be described, tf,fractured time,can also be recorded by the test which is taken as a electrochemical behavior and mechanical property for SCC resistance evaluation. Test environment:143°C boiling 42%MgCl2 solution is used.Besides, micro analysis were conducted with light microscopy(LM),SEM,TEM,and Auger energy spectrum(AES) so as to reveal the correlation between the data generated by the CLTT results and micro analysis.

High Resolution Low Loss Microscopy of Crystalline Surfaces

1980 ◽  
Vol 38 ◽  
pp. 162-163
Author(s):  
William Krakow ◽  
Alec N. Broers
Keyword(s):  
Electron Microscopy ◽  
High Resolution ◽  
Surface Topography ◽  
Secondary Electron ◽  
Objective Lens ◽  
Surface Imaging ◽  
Low Loss ◽  
Fine Grained ◽  
Scanning Electron ◽  
Crystalline Surfaces

Low-loss scanning electron microscopy can be used to investigate the surface topography of solid specimens and provides enhanced image contrast over secondary electron images. A high resolution-condenser objective lens has allowed the low-loss technique to resolve separations of Au nucleii of 50Å and smaller dimensions of 25Å in samples coated with a fine grained carbon-Au-palladium layer. An estimate of the surface topography of fine grained vapor deposited materials (20 - 100Å) and the surface topography of underlying single crystal Si in the 1000 - 2000Å range has also been investigated. Surface imaging has also been performed on single crystals using diffracted electrons scattered through 10−2 rad in a conventional TEM. However, severe tilting of the specimen is required which degrades the resolution 15 to 100 fold due to image forshortening.

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